Induction heat cooking apparatus to implement WPT and PFC power converter

Abstract

An induction heat cooking apparatus that includes: a rectifier that is configured to convert alternating current (AC) voltage supplied from an external power source into direct current (DC) voltage; an inverter that is configured to generate current based on DC voltage received from the rectifier and provide the current to output nodes; heating coils that are configured to, based on the current generated by the inverter, generate magnetic fields for providing heat; a first capacitive unit that includes one or more resonance capacitors and that is coupled between the output nodes; a second capacitive unit that includes one or more wireless power transfer (WPT) capacitors and that is configured to be coupled between the output nodes; and a mode conversion switch that is configured to couple the second capacitive unit to the first capacitive unit in parallel is disclosed.

The invention claimed is: 
     
       1. An induction heat cooking apparatus comprising:
 a rectifier configured to convert an alternative current (AC) voltage supplied from an external power source into a direct current (DC) voltage; 
 an inverter configured to receive the voltage from the rectifier to supply current to heating coils, wherein the heating coils are configured to generate magnetic fields when the current flows by the inverter; 
 a resonance capacitor comprising a plurality of capacitors connected to each other and connected to DC terminals to which the voltage is outputted from the rectifier; 
 a wireless power transfer (WPT) capacitor connected in parallel to the resonance capacitor; and 
 a mode conversion switch configured to be connected between the resonance capacitor and the WPT capacitor, 
 wherein the mode conversion switch is configured to be opened in a cooking device heating mode and closed in a wireless power transfer mode. 
 
     
     
       2. The induction heat cooking apparatus according to  claim 1 , further comprising a driving unit configured to control a closed/opened state of the mode conversion switch,
 wherein, when the mode conversion switch is closed, the resonance capacitor and the WPT capacitor are connected in parallel to each other, and 
 when the mode conversion switch is opened, the resonance capacitor and the WPT capacitor are not connected to each other. 
 
     
     
       3. The induction heat cooking apparatus according to  claim 1 , further comprising a sensor unit configured to recognize a kind of product disposed on the induction heat cooking apparatus,
 wherein the mode conversion switch is opened when the recognized product by the sensor unit is a product for heating and closed when the recognized product by the sensor unit is a product for receiving wireless power. 
 
     
     
       4. The induction heat cooking apparatus according to  claim 1 , further comprising an interface unit configured to receive an operation mode of the induction heat cooking apparatus,
 wherein the mode conversion switch is configured to be (i) opened when the received operation mode by the interface unit is the cooking device heating mode and (ii) closed when the received operation mode by the interface unit is the wireless power transfer mode. 
 
     
     
       5. A system comprising:
 the induction heat cooking apparatus according to  claim 2 ; and 
 a secondary-side product, 
 wherein the secondary-side product is heated or receives wireless power according to an operation of the mode conversion switch. 
 
     
     
       6. The system according to  claim 5 , wherein the secondary-side product comprises a wireless power receiving device. 
     
     
       7. The system according to  claim 6 , wherein the wireless power receiving device is an electric heater. 
     
     
       8. The system according to  claim 7 , wherein the wireless power receiving device comprises:
 a receiving coil configured to receive AC power from the heating coils; and 
 a fixed load configured to be driven by using the received AC power. 
 
     
     
       9. The system according to  claim 6 , wherein the wireless power receiving device is a device including a motor. 
     
     
       10. The system according to  claim 9 , wherein the wireless power receiving device comprises:
 a receiving coil configured to receive AC power from the induction heat cooking apparatus; 
 a variable load driven in a state in which a resistance value is not fixed; and 
 a power factor correction (PFC) power converter configured to output a fixed voltage to the variable load by using the AC power supplied through the receiving coil. 
 
     
     
       11. The system according to  claim 10 , wherein the PFC power converter comprises:
 a secondary rectifier configured to rectify the AC power supplied through the receiving coil into DC power; and 
 a PFC circuit configured to output the fixed voltage by using a waveform rectified through the secondary rectifier. 
 
     
     
       12. The system according to  claim 11 , wherein the PFC circuit comprises:
 an inductor configured to receive an input voltage from the secondary rectifier; 
 a field-effect transistor (FET) switch configured to charge current into the inductor in a turn-on state and discharge the current charged in the inductor in a turn-off state; 
 a PFC controller configured to control operation of the FET switch; and 
 an output capacitor, to which a voltage higher than the input voltage is applied when the current is discharged according to the operation of the FET switch, and absorbing a high frequency. 
 
     
     
       13. The system according to  claim 11 , wherein the secondary rectifier is configured to be formed a diode bridge.